The dreaded 7H fault. You will come across this fault when you’re commissioning, and it’s usually down to error in the system. So 80 percent of the time it’s going to be down to an error issue in the system itself. It can reset itself sometimes. And if you go to reset, if you press the button on the left-hand side and press reset, it sometimes takes a little while to reset itself.
Sizing an air source heat pump correctly is extremely important if the heat pump is going to do its job. In this video Jamie talks about why this is and gives a brief description of how correct sizing is done.